Events at Physics |
Events During the Week of October 6th through October 13th, 2024
Monday, October 7th, 2024
- Climate & Diversity
- Climate and Diversity Committee Open Hours
- Time: 12:00 pm - 2:00 pm
- Place: Chamberlin 5310
- Speaker: Rachel Zizmann, UW-Madison Physics
- Abstract: Open Hours are welcome for everyone in the department! During these sessions, we have the option to discuss the topic listed, that is not required or necessary for attending
- Host: Rachel Zizmann
- Preliminary Exam
- Search for TeV Halos Using HAWC Data
- Time: 3:00 pm - 5:00 pm
- Place: 5280 Chamberlin Hall
- Speaker: Hongyi Wu, Physics PhD Graduate Student
- Abstract: Extended gamma-ray emission at TeV energies, known as TeV halos, has been observed around a few middle-aged isolated pulsars. It has been suggested that they may also be powered by millisecond pulsars (MSPs). Using data from the High Altitude Water Cherenkov (HAWC) Observatory, we searched for extended gamma-ray emission around 36 isolated middle-aged pulsars and 57 MSPs. Through a stacking analysis comparing TeV flux models against a background-only hypothesis, we identified TeV halo-like emission from isolated middle-aged pulsars at a significance level of 5.10σ, but found no significant emission from MSPs. The results imply that TeV halos may commonly exist around middle-aged pulsars, while MSPs are not as efficient in producing them. These findings provide a method to identify pulsars that are invisible to radio, X-ray, and GeV gamma-ray observations, and have significant implications for the physics interpretation of the Galactic center GeV excess and high-latitude Galactic diffuse emission. Future works including HAWC and Fermi-LAT data analysis around TeV halo sources will also be discussed.
- Host: Ke Fang
- Theory Seminar (High Energy/Cosmology)
- Machine Learning Symmetries in Physics from First Principles
- Time: 4:30 pm - 5:30 pm
- Place: 5310 Chamberlin Hall
- Speaker: Konstantin Matchev, University of Florida
- Abstract: Symmetries are the cornerstones of modern theoretical physics, as they imply fundamental conservation laws. The recent boom in AI algorithms and their successful application to high-dimensional large datasets from all aspects of life motivates us to approach the problem of discovery and identification of symmetries in physics as a machine-learning task. In a series of papers, we have developed and tested a deep-learning algorithm for the discovery and identification of the continuous group of symmetries present in a labeled dataset. We use fully connected neural network architectures to model the symmetry transformations and the corresponding generators. Our proposed loss functions ensure that the applied transformations are symmetries and that the corresponding set of generators is orthonormal and forms a closed algebra. One variant of our method is designed to discover symmetries in a reduced-dimensionality latent space, while another variant is capable of obtaining the generators in the canonical sparse representation. Our procedure is completely agnostic and has been validated with several examples illustrating the discovery of the symmetries behind the orthogonal, unitary, Lorentz, and exceptional Lie groups.
- Host: Lisa Everett
Tuesday, October 8th, 2024
- Astronomy Colloquium
- ALMA and JWST team up to understand the formation of planets
- Time: 10:00 am - 11:00 am
- Place: WiCOR 6th Floor Sterling
- Speaker: Dr. Nicolas Kurtovic, Max Planck Institute for Extraterrestrial Physics
- Abstract: Exoplanets are a common outcome of the star-formation process. Some of the most relevant properties of planetary systems are set during their formation: the number of planets, mass, architecture, and composition. In this talk, I will focus on what we have learned about planet formation on the most common type of stars: late M-dwarfs and binaries, and how the combination of ALMA with JWST/MIRI gives us a full picture of the planet-formation environment.
- Host: Ke Zhang
- Theory Seminar (High Energy/Cosmology)
- Physical Signatures of Fermion-Coupled Axions
- Time: 11:00 am - 12:00 pm
- Place: 5310 Chamberlin Hall
- Speaker: Alexander J. Millar, Fermilab
- Abstract: While there is an abundance of experiments searching for axion dark matter (DM) via its electromagnetic coupling, there are fewer utilizing its derivative coupling to electrons and nucleons. This direct coupling generates dynamical effects through the fermion spin, and therefore spin-polarized targets are a naturally useful target. We propose using spin-polarized or magnetized analogs of layered dielectric haloscopes, which are sensitive to axions through their coupling to electrons. These novel techniques can be powerful probes at both radio frequencies, with sensitivity to currently unexplored parameter space, and optical frequencies, with sensitivity comparable to current astrophysical bounds.
- Host: Yang Bai
- Physics Education Innovation Seminar
- Use of inclusive teaching practices to improve teamwork and communication skills in STEM education
- Time: 1:00 pm - 2:00 pm
- Place: Sterling B343
- Speaker: Angela Kita and Christa Wille, Center for Innovation in Engineering Education, University of Wisconsin-Madison
- Abstract: Zoom Meeting ID: 912 1127 1606
STEM professionals need to be skilled in teamwork and communication to be most effective in the workplace. Course content is often focused on disciplinary technical skills, with less focus placed on ensuring students have the professional skills they need to succeed. Modeling the instruction of professional skills through the use of inclusive teaching practices contributes to students’ growth by improving team dynamics and student learning outcomes, and in turn reduces the time instructors spend managing teams. In this session we will share specific examples of inclusive teaching strategies used to instruct teamwork such as team contracts for setting expectations in teams and strategies to encourage peer feedback. We will also briefly share on the development of the Engineering4All community of practice that we have created in the College of Engineering to support instructors and the integration of professional skills such as teamwork and communication in STEM education.
Speaker Bios:
Angela Kita (she/her) is committed to improving learning experiences for all students through classroom innovation, program development, and fostering community. Her passion for all things teaching and learning began through teaching experiences as a graduate student, particularly working with non-biology majors exploring the various systems and structures found in animal phylogeny. She has worked collaboratively with faculty and staff on curriculum development, improved instructor support, and cross-campus projects. As a member of the Center for Innovation in Engineering Education, she is excited to build and grow partnerships that better connect students to their learning, their passions, and their goals.
Ph.D. Cellular and Molecular Biology (University of Wisconsin, Madison); B.S. Molecular and Cell Biology (University of California, Berkeley)
Christa Wille (she/her) is passionate about using research to advance teaching and learning in higher education, especially in engineering. Through her lived experiences as a learner across multiple disciplines, her leadership in instructional design of a flipped classroom in her biomechanics courses, and her extensive background in research, Christa is well suited to support scholarship of teaching and learning projects in the College of Engineering. As a member of the Center for Innovation in Engineering Education, she is eager to help use research to advocate for and support educational practices that ensure inclusive and effective teaching and learning practices for all engineering students and instructors alike.
Ph.D. Biomedical Engineering (University of Wisconsin, Madison); M.S. Biomedical Engineering (University of Wisconsin, Madison); Doctor of Physical Therapy (University of Wisconsin, Madison); B.S. Biomedical Engineering (University of Wisconsin, Madison) - Host: Carrie Francis
- Wisconsin Quantum Institute
- Quantum Coffee Hour
- Time: 3:00 pm - 4:00 pm
- Place: Rm.5294, Chamberlin Hall
- Abstract: Please join us for the WQI Quantum Coffee today at 3PM in the Physics Faculty Lounge (Rm.5294 in Chamberlin Hall). This series, which takes place approximately every other Tuesday, aims to foster a casual and collaborative atmosphere where faculty, post-docs, students, and anyone with an interest in quantum information sciences can come together. There will be coffee and treats.
- Worlds in the Making: Origins of Stars, Planets, and Life
- From Astronomy to Chemistry: Towards a Continuous Path for the Origins of Life
- Time: 7:00 pm - 8:00 pm
- Place: Space Place
- Speaker: Zoe Todd, UW-Madison
- Abstract: A series of talks by UW-Madison scientists from the Wisconsin Center for Origins Research (WiCOR), hosted by UW Space Place.
- Host: Jim Lattis
Wednesday, October 9th, 2024
- Preliminary Exam
- Connecting Multimessenger Observations to Theory in Particle Astrophysics from GeV to EeV
- Time: 11:00 am - 1:00 pm
- Place: 5280 Chamberlin Hall or
- Speaker: Angelina Partenheimer, Physics PhD Graduate Student
- Abstract: In my preliminary exam, I will discuss my paper on ultrahigh energy cosmic rays from gamma-ray sources. Ultra-high-energy cosmic rays (UHECRs) are the highest-energy particles ever observed. While the sources producing UHECRs are still unknown, the Pierre Auger Observatory has detected a large-scale dipole anisotropy in the arrival directions of cosmic rays above 8 EeV. My project explores whether resolved gamma-ray sources can reproduce the Auger dipole. I find that in all cases, the simulated dipole has an amplitude significantly larger than that measured by Auger, implying that the resolved gamma-ray sources are insufficient to account for the population of sources producing the highest-energy cosmic rays. Next, I will discuss my recent project on prospects of detecting GeV transients with IceCube DeepCore and Upgrade. A wide variety of transient sources have been predicted to emit GeV neutrinos. In light of the upcoming IceCube-Upgrade, which will extend the IceCube detector’s sensitivity down to a few GeV, I survey a variety of transient source models and compare the predictions and detector sensitivities. Finally, I will briefly discuss my intended thesis work, which involves using anticipated UHE neutrino data from the Payload for Ultrahigh Energy Observations balloon experiment to constrain the UHECR proton composition.
- Host: Ke Fang
- Theory Seminar (High Energy/Cosmology)
- 6220 Nesbitt Rd, Fitchburg, WI 53719
- Time: 4:00 pm - 5:00 pm
- Place: 5280 Chamberlin Hall
- Speaker: Cash Hauptmann, University of Nebraska–Lincoln
- Abstract: I will discuss ongoing work concerning cosmological phase transitions (PTs) and their possible roles in the production of dark matter (DM) and primordial black holes (PBHs). For DM, I have recently proposed a non-thermal production mechanism utilizing supercooled first-order PTs which can enhance the abundance of DM. This enhancement opens the viable DM parameter space to models with higher annihilation cross sections which would have otherwise produced too little DM in the standard thermal scenario. Another interesting consequence of first-order PTs could be an efficient trapping of DM in false vacuum domains, and their subsequent collapse to PBHs. Depending on the energy scale of the PT, these PBHs could make up significant fractions (if not all) of today’s DM abundance. Whatever their byproducts may be, first-order PTs are expected to source stochastic background signals of gravitational waves—potentially probeable by next-generation detectors. With this in mind, all phenomenological results are presented in a robust multi-messenger fashion; correlating DM or PBH constraints with gravitational wave signals.
- Host: Lisa Everett
Thursday, October 10th, 2024
- R. G. Herb Condensed Matter Seminar
- An Electron Linear Accelerator for On-Demand Qubit Irradiation
- Time: 10:00 am - 11:00 am
- Place: 5310 Chamberlin
- Speaker: Dwight Luhman, Sandia National Labs
- Host: Mark Eriksson
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- A stress test of Galactic cosmic rays
- Time: 2:30 pm - 3:30 pm
- Place: Chamberlin 5280 /
- Speaker: Philipp Mertsch, RWTH Aachen University
- Abstract: The Galaxy is pervaded by a flux of high-energy, non-thermal particles: cosmic rays. The last years have seen great progress towards elucidating the century-old questions of cosmic ray origin. Yet, a number of anomalies point to more complex dynamics than previously thought. With new and upcoming data, we are in a position to put some stress on the standard picture of cosmic rays and address some of the fundamental questions: What is the energy of transition from Galactic to extra-Galactic sources? How is magnetised turbulence shaping the spectra and anisotropies of cosmic rays? And what is the feedback of cosmic rays on their environments? In this talk, I will describe some of our recent works in that direction. Diffuse emission in high-energy gamma-rays and neutrinos, as measured by experiments like IceCube at the South Pole, is a great tool for studying cosmic rays elsewhere in the Galaxy. We have recently provided new predictions for gamma-rays and neutrinos, including properly evaluated model uncertainties. I will address the need for better gas maps and explain how we used Bayesian inference in producing the highest resolution 3D maps of atomic and molecular hydrogen in the Galaxy to date.
- Host: Paolo Desiati
- Astronomy Colloquium
- Our Chemical Origins: Tracing the History of Cold and Hot Gas During Planet Formation
- Time: 3:30 pm - 4:30 pm
- Place: 4421 Sterling Hall
- Speaker: Abygail Waggoner, UW-Madison
- Abstract: The gas and dust of protoplanetary disks are a window into the history of the Solar System and extrasolar planetary systems, but there are still many aspects of the chemistry in these planet forming regions that are not well understood. This talk will be divided into two questions that, when combined, will provide a clearer picture of the gasses available to forming planets. These questions are: 1) How does the central star (and X-ray flaring events in particular) impact the cold gas? 2) How does the hot gas close to the star evolve over time? To answer these questions, I will present a combination of results and future projects using chemical-disk models and observations from ALMA, SMA, and JWST observing facilities.
- Host: Melinda Soares-Furtado
Friday, October 11th, 2024
- Black and Brown in Physics
- BBiP General Meeting
- Time: 1:00 pm - 2:15 pm
- Place: Sterling B343
- Speaker: Taylor Bailey, Rebecca M. Blank Center for Campus History (CCH)
- Abstract: The Black and Brown in Physics RSO (BBiP) would like to invite you to our next General Meeting happening Friday, October 11 at 1 PM in Sterling B343. As a continuation of our celebration of Hispanic heritage month, we are inviting Taylor Bailey, the director of the Rebecca M. Blank Center for Campus History (CCH), to give a lecture on Latine history at UW-Madison titled “Latine Resistance at UW-Madison”. We also have a Zoom link for anyone who is unable to make the meeting in-person:
- Host: Faizah Siddique
- Physics Department Colloquium
- How national lab science advances economic and national security
- Time: 3:30 pm - 4:30 pm
- Place: Chamberlin 2241
- Speaker: Sean Jones, Argonne National Laboratory
- Host: Pupa Gilbert
